This is an area where the accelerometer can SHINE.

In this case, the user interface is far to large to confortably fit on a tiny screen. Imagine, tilting the device to scroll around interface quickly and naturally, as you fiddle with all of those knobs/sliders. Thus the N900 screen only sees a portion of the full interface, and you slide around it to gain access to the whole thing.

Before you write off the idea as lunacy, consider that Quake3 on the N900 has tilt-to-slide-about controls, and they're useful enough to play! I bet with a little practice this interaction method will become very natural!

}:^)~